Conventionally, in a heat treatment device for synthetic fiber filament yarns that is to be installed as one of constituent parts of a drawing and texturing device for thermoplastic synthetic fiber filament yarns together with other constituent parts and that utilizes characteristics of saturated steam of heat medium liquid, it has been required due to said characteristics to provide a boiler for heating the heat medium liquid and said boiler is disposed below a closed container of the saturated steam, and also a heating surface facing the filament yarns and having a length corresponding to that of the filament yarns is required in order to heat the filament yarns at a predetermined temperature during traveling. Therefore, the closed container of the saturated steam is formed necessarily longer in vertical direction as described in JP-A-11-93027, for example.
This heat treatment device is installed as one of constituent parts of the drawing and texturing device for synthetic fiber filament yarns together with other constituent parts as described above. Consequently, the overall height of the apparatus increases and which makes it difficult to acquire a building in which the apparatus can be installed.
This tendency is remarkable particularly when a feeding speed of the filament yarns is increased to increase the heating capacity to heat the synthetic fiber filament yarns.
To reduce the height of the building in which the heat treatment device for the synthetic fiber filament yarns is installed, on the one hand, it may be conceivable to form the closed container constituting a chamber of the saturated steam to be longer in horizontal direction as a whole and to arrange its heating surface to face downwardly. According to such a construction, however, since the condensed liquid of the synthetic fiber builds up on the bottom surface neighboring to the heating surface and inside the closed container of the saturated steam, heating of the synthetic fiber by the saturated steam is impeded.
In the above-mentioned heat treatment device, a boiler is installed for each additional closed container. Therefore, when the number of the closed containers is increased to increase the capacity, the number of the boilers must be increased correspondingly and the cost increases as much.
In the heat treatment device for synthetic fiber filament yarns by utilizing the characteristics of the saturated steam of the heat medium liquid described above, it is an object of the present invention to make the height of the closed container constituting the heat treatment device smaller than the full length of the closed container so that the height of a building for accommodating overall devices is lowered when the heat treatment device is installed together with other devices, thereby making it easier to acquire the building for this purpose.
It is another object of the present invention to make it unnecessary to increase correspondingly the number of boilers for heating a heat medium liquid inside a closed container when the number of the closed container is increased to increase the capacity, thereby reducing the cost for additional boilers.
It is still another object of the present invention to make it easy to thread synthetic fiber filament yarns by handwork onto a heating surface of a closed container constituting the heating device described above.